Print the first four characters of hostname

Shell Programming and Scripting
1

Hey,
I'm trying to print the first four characters of the hostname of a computer.

I can get it from using:
hostname -s | sed 's/...........$//'"

but this is when I know how many characters are in the computer name.

I dont understand why some like:
hostname -s | sed '/..../p'
wont work?

Any ideas?

Thanks.

2 
hostname -s|cut -c 1-4
3

Thanks Mate! I have spent a number of hour trying to find this out?

4

Hi.

Because that sed line says: "If the incoming line has 4 characters then print it."

If you wanted to print just the first 4 with sed, you could use:

hostname -s | sed 's/^\(....\).*/\1/'

which seems cumbersome compared to the cut, but sed is capable of much more than cut ... cheers, drl

5

can try this also

hostname|awk '{print substr($1,1,4)}'

Thanks.

6

Last 4 characters how can i print

7

using a similar idea(s) as above......

8

Though longer than some other solutions, this will be much faster because it doesn't use any external commands other than hostname:

hostname=$(hostname)
temp=${hostname#????}
echo ${hostname%"$temp"}

But it is also possible that your shell already has the output of hostname in the variable $HOSTNAME (bash does), and you don't need any external command:

temp=${HOSTNAME#????}
echo ${HOSTNAME%"$temp"}